private void btnAddWindow_Click(object sender, System.EventArgs e)
{
// Are any text fields blank?
if (txtLeft.Text.Length == 0 || txtTop.Text.Length == 0 ||
txtWidth.Text.Length == 0 || txtHeight.Text.Length == 0)
{
MessageBox.Show("Please fill in all text boxes",
"Error",
MessageBoxButtons.OK,
MessageBoxIcon.Error);
return;
}
ChildForm aChildForm = new ChildForm();
aChildForm.Owner = this;
aChildForm.DesktopBounds = new Rectangle(
Int32.Parse(txtLeft.Text),
Int32.Parse(txtTop.Text),
Int32.Parse(txtWidth.Text),
Int32.Parse(txtHeight.Text));
aChildForm.Show();
// Create a new delegate for the child form's Repaint method
ChangeColorDelegate newDelegate = new ChangeColorDelegate(aChildForm.Repaint);
// Combine new delegate into the multicast delegate
mAllRepaintMethods = (ChangeColorDelegate)System.Delegate.Combine(mAllRepaintMethods,
newDelegate);
// Use multicast delegate to count the child forms
sbStatus.Text = "Created child form " +
mAllRepaintMethods.GetInvocationList().Length + ".";
}
private void ChangeColorThreadSafe(Color c)
{
if (button1.InvokeRequired)
{
ChangeColorDelegate delgate = new ChangeColorDelegate(ChangeColorThreadSafe);
button1.Invoke(delgate, new object[] { c });
}
else
{
this.BackColor = c;
}
}
// Constructor
public MainForm()
{
InitializeComponent();
alphabet.Add(0, "hello");
alphabet.Add(1, "world");
alphabet.Add(2, "I am");
alphabet.Add(3, "student");
alphabet.Add(4, "good");
alphabet.Add(5, "bye");
alphabet.Add(10, " ");
comboCalculateNewColor.SelectedIndex = 0;
_changeColorDelegate = this.ChangeColor;
}
public void ChildFormClosing(ChildForm aChildForm)
{
// Create a delegate for the ChildForm that is closing
ChangeColorDelegate unneededDelegate = new ChangeColorDelegate(aChildForm.Repaint);
// Remove the delegate from the multicast delegate
mAllRepaintMethods = (ChangeColorDelegate)System.Delegate.Remove(mAllRepaintMethods, unneededDelegate);
// If multicast delegate is Nothing, there are no child forms left
if (mAllRepaintMethods == null)
{
sbStatus.Text = "Final child form has been closed.";
}
else
{
// Use multicast delegate to count the child forms
sbStatus.Text = "Child form closed, " + mAllRepaintMethods.GetInvocationList().Length + " form(s) remaining.";
}
}
